Band saw attachment for producing propeller blanks



Feb; 21, 1950 H. B. DANIEL 2,497,869

' BAND SAW ATTACHMENT FOR PRODUCING PROPELLER BLANKS Filed Nov. 6, 1944 i Z325 6g. 898

Patented Feb. 21, 19 50 BAND SAW ATTACHMENT FOR PRODUCING PROPELLER BLANKS Henry Brent. Daniel, Takoma Park, Md.

Application November 6, 1944, Serial No. 562,226

ard band-saw for guiding material in a predetermined path with respect to the band-saw for insuring successive cutting of blanks in predetermined shape from the material for use in the construction of aeroplane propellers.

A still further object of my invention is to provide a construction of attachment for the table of a standard band-saw in which a reciprocating support carrying the material from which propeller blanks are to be produced is successively guided through predetermined angular paths for successively sawing propeller blanks from the material in a shape having the required pitch for production of aeroplane propellers.

Another object of my invention is to provide a construction of adjustable attachment for the table of band-saws in which material usable in the construction of aeroplane propellers may be successively sawed to produce aeroplane propeller blanks shaped in accordance with the required pitch of the propeller blades.

Other and further objects of my invention reside in the construction of an attachment for band-saws for producing aeroplane propeller blanks inexpensively on a quantity production.

scale as set forth more fully in the specification hereinafter following by reference to the accompanying drawings in which:

Figure 1 is a top plan view of the attachment for band-saws clamped in position upon the table of a band-saw table, the band-saw being illustrated in transverse section and the material from which aeroplane ropeller blanks are to be formed being removed from the attachment to enable the mechanism of the attachment to be shown more clearly; Fig. 2 is a side elevational View of the attachment shown in Fig. 1, the table of the band-saw being illustrated in transverse section and a fragmentary portionof the bandsaw being illustrated in sidev elevation; Fig. 3 is an end view or the band-saw attachment of my invention looking at the end at the left of Figs. 1 and 2 and showing the manual grip means in end elevation which is grasped for the purpose of imparting reciprocal movement to the frame of the attachment for moving the material to be sawed. in successive strokes: toward and away 2 Claims. (01. 144145) from the band-saw; Fig. 4 is an end elevational view'of the attachment looking at the right-hand end of the attachment illustrated in Figs. 1 and 2 and showing the templet which is provided to control the angular displacement of the material to he sawed; Fig. 5 is a transverse sectional view through the attachment taken substantially :on line 5-5 of Fig. 2 and showing the material from which propeller blanks are to be formed clamped in position upon the angularly displaceable tilting table of the attachment and showing in dotted lines a path of movement of the tilting table in the course of the saw stroke which pro- .duces the propeller blank. of required pitch; and

:Fig. 6 is a vertical sectional View taken on line fi -ii of Fig; 2 and illustrating more clearly the coupling means between the templet and the tilting table by which the angular displacement of the tilting table is successively controlled.

My invention is directed to a construction of attachment which may be readily applied to a standard band-saw table for clamping material from which propeller blanks are to be produced and directing the material in successive longi tudinal strokes toward and away from the continuously moving band-saw. The attachment ineludes an adjustablefram'e which may be applied to band-saw tables of various sizes and which serves as a support for a tiltingtable. The tilting table is pivotally mounted in a reciprocative frame which is guided by the clamping means which supports the attachment with respect to the band-saw table. The tilting table is guided through a predetermined angular displacement by means of a templet coupled to one end of the tilting table and guided by the frame which is secured to the band-saw table through a path corresponding to the pitch of the propeller blank to be produced. The material from which the propeller blanks are to be formed is clamped to the tilting table and is subjected to successive sawing operations as the tilting table is simul tane'ously moved longitudinally and angularly with respect to the band-saw.

I have found the attachment of my invention highly practical in its construction for the production of propeller blanks. While I have described my invention in one of its preferred embodiments, I desire that the description herein be regarded in the illustrative sense and not in the limiting sense, as I realize that modifications in detail of the structure of my invention may be made without departing from the spirit of my invention.

Referring to the drawings in more detail, the

table of the band-saw is represented by reference character I, to which the transversely extending clamp represented at 2 is secured. The clamp 2 comprises a pair of transversely extending rail members 3 and 4 which have downwardly and inwardly extending ends 3a and 4a, which clamp beneath the flanged table of the band-saw indicated at I. The rail members 3 and 4 constitute an adjustable frame that may be applied to bandsaw tables of various sizes and which serves as a support for the tilting table. The transversely extending rail members 3 and 4 project beyond the opposite flanged edge of the table I and terminate in slots represented at 3b and 41). An end support 5 is provided having a pair of aligned projections B and I thereon which extend beneath the projecting ends of the transverse rail members 3 and 4 respectively, and establish clamping connection with the table I of the bandsaw as represented at Go and Ia. Bolt members 8 and 9 extend through the extensions 5 and I respectively and pass through the slots 32; and 4b in the transverse rail members 3 and 4, and are secured in clamping relation with respect to the table I by means of wing nuts 8a and 90.

Each of the transverse rail members 3 and 4 is undercut as represented at 30 and 4c and serves as guide rails for the base plate I0, which is cut out at its center as represented at Illa. and provided with an opening IOb at one side thereof to facilitate installation of the base I on the table I of the band-saw around the band-saw blade represented at I I. The table I has been indicated as provided with an opening I2 for the band-saw blade connected with the slit M to permit the band-saw blade II to be readily installed and removed.

A suitable guide I for the band-saw has been illustrated in Fig. 5. The table I is provided with the customary angular adjustment means represented generally at I6, and a clamping screw device indicated generally at H to facilitate the angular adjustment of the table I in association with the adjustable clamp I8 carried on frame I9.

It will be understood that reference to the band-saw plate and band-saw table is made herein merely for the purpose of explaining the attachments to my invention.

The base plate In is slidable transversely of the band-saw table beneath the guide rails 30 and 40 with which the grooved portions I00 and Id of the base plate ID coact. The base plate It] carries on one end thereof the vertically extending bearing support which forms a pivotal support for the tilting table shown at 2|. The opposite end of the tilting table 2| is pivotally mounted in a bearing support represented by 22 carried by base plate I II. The pivotal mounting of the tilting table is effected by means of transverse members 2 Ia and 2 I b carried by opposite ends of the tilting table 2I, and provided with oppositely extending studs 2 I0 and 2 Id located adjacent to table 2I and which extend through journals in the supports 29 and 22, respectively. Stud 2Ic is relatively short, while stud 2 Id is somewhat longer and has the end thereof engaged by an adjustable coupling member 23 by means of set screws 24 therein. The set screw .24 looks the coupling member 23 to the stud 2Id.

The coupling member 23 includes a slot 25 in the enlarged end thereof with which set screw 26, screw threaded into the coupling member 23 as shown, coacts. The slot 25 receives the end of the metallic templet 21 which is locked therein by means of set screw 26. The templet 21 is formed from hardened metal in the contour of the airplane propeller blanks to be produced on the band-saw. That is to say, the metallic templet 21 is axially twisted as represented in 27a in accordance with the pitch of the propeller blanks to be produced. The templet 21 is supported for longitudinal sliding movement between the pair of vertically journalled roller members 28 and 29. Roller members 28 and 29 are rotatively journalled on screw members 30 and 3| which pass through the U-shaped lug 32 forming a spacer member for the roller members 28 and 29 with respect to the frame 5. As the templet passes between roller members 28 and 23, angular movement is imparted to stud 2Id through coupling 23 for imparting corresponding angular movement to the tilting table 2|.

The tilting table 2| is provided with a transversely extending member 33 which is transverse- 1y slotted as represented in 33a and calibrated as represented at 33b. The calibrations 33b serve as a reference scale for the dimensional setting of wood block 36 on the tilting table 2I. The transverse slot 33a serves as a guide for the adjustable thumb screw 34 which serves as an adjustable securing means for the clamp 35. The clamp 35 serves as a means for securing the wood block 36 shown more clearly in Fig. 5 in position on the tilting table 2!. It will be observed that the tilting table 2| has one edge thereof 31 formed on a bias with the under-surface of the edge out on an angle as represented at 31a to allow adequate clearance for the angular sawing of the blank from the block 36 and to permit the longitudinal advance of the block with respect to the band-saw I I while permitting sufficient clearance around the block for efiecting the manual position ng thereof.

Thus it will be seen that the base plate Ii] may be transversely advanced and retracted by pushing and pulling upon control knob 38 attached to the vertically extending bearing support 20 between the rail members 3 and 4 in the process of successively cutting twisted blanks from the wood block 36. As the base plate I0 is reciprocated, tilting table 2I is automatically angularly shifted in a pre-determined path under control of the twisted templet 21 operating through the roller members 28 and 29. Block 36 from which the airplane propeller blanks are to be cut is then periodically shifted from the start position illustrated in Fig. 5 by dotted line 39a, through the intermediate position illustrated by the full line position 3% to the limiting position indicated by dotted lines 390 to out successive propeller blanks in twisted contour from the block 36.

Thus propeller blanks are cut on a quantity basis at a very substantial production rate. Blocks are readily replenishable by clamping the blocks in position under the clamp 35.

While I have shown the equipment of my invention arranged for manual operation, it will be understood that reciprocative movement may be imparted to the base plate In through an automatically driven motor means for performing successive repeat operations and speeding up the production process.

It will be understood that relative dimensions of the attachment of my invention are not critical and that variations may be made in size and shape of the parts for accommodating the attachment to various sized band-saws and for producin various sized propeller blanks. I have intended by the illustrations and description herein to set forth my invention generically and I desire that it be understood that no limitations upon my invention are intended other than may be imposed by the scope of the appended claims.

What I claim and desire to secure by Letters Patent of the United States is as follows:

1. Apparatus for sawing aeroplane propeller blanks comprising in combination with a bandsaw including a driven band-saw and a work supporting table, a two-part clamp attachable to said work supporting table on opposite sides of said band-saw, said clamp including a pair of guide rails, a slide extending on opposite sides of said band-saw and confined by said guide rails for reciprocative movement toward and away from the band-saw in a plane substantially normal to the plane of said band-saw, supports carried by said slide, a. tilting substantially flat plane-like table pivotally mounted in said supports, a templet in the form of a spirally twisted strip member coupled to said tilting table and extending through a portion of said two-part clamp for imparting angular movement to said tilting table as said slide advances toward the band-saw and means for clamping material to be sawed on said tilting table whereby shaped blanks may be severed from said material having an axial twist simulating an aeroplane propeller.

2. Apparatus for forming aeroplane propeller blanks comprising in combination with the bandsaw and table of a band-saw, an adjustable frame attachable to the band-saw table, a slide mounted in said frame for longitudinal reciprocative movement therein toward and away from the band-saw in a plane substantially normal to the plane of said band-saw, said slide being open at one edge thereof for entry of the band-saw, a tilting substantially flat plane-like table carried by said slide, said tilting table having the edge thereof adjacent the band-saw formed on a bias spaced in all positions from the band-saw, means for securing material to be cut by said band-saw to said tilting table and an axially twisted flat strip member connected to said tilting table and slidable through a shaped portion of said frame for shifting the tilting table and the material carried thereby through a predetermined angular path as the slide advances toward the band-saw for severing shaped blanks from said material having an axial twist simulating the pitch of an aeroplane propeller.

HENRY BRENT DANIEL.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 281,856 Fifield July 24, 1883 284,512 Tait Sept. 4, 1883 324,669 Donecker Aug. 18, 1885 661,696 Holtmann Nov. 13, 1900 860,486 King July 16, 1907 899,356 Trevor Sept. 22, 1908 1,275,160 Emery Aug. 6, 1918 1,728,030 Bielski Sept. 10, 1929 2,227,965 Dunn Jan. 7, 1941 2,346,866 Pelphrey Apr. 18, 1944 

